This research is to expand our knowledge of impression management generally and the process of lying and the nonautomated detection of lying specifically. In the major study naive subjects will lie or tell the truth during portions of a simulated job interview. The actor wil be videotpaed and observer subjects will try to guess when he is lying. The observers' judgments will be analysed for consensus and accuracy. Next, verbal and nonverbal stimulus characteristics which are associated with either the actual truth of an answer or observers' judgments of its truthfulness will be examined. The approach used is social psychophysical, in which physical characteristics of the interviews are measured or rated by independent judges. Pilot studies suggest that naive observers can be both consensual and accurate in judging deception and may base their judgements on an answer's length, concreteness, plausibility, and latency and the number of smiles and speech errors occurring in it. However, some nonverbal cues, such as a hesitation prior to answering, have no consistent meaning, but amplify the suspiciousness of a statement, by increasing the credibility of a self-damaging statement and decreasing the credibility of a self-serving one. Follow up experiments to the main study will manipulate selected verbal and nonverbal cues to determine their effects on deception judgments. Another experiment will manipulate verbal and nonverbal deception cues in a suspicion allaying and a suspicion provoking conversation to test the proposition that verbal and nonverbal cues can be equally useful in indicating deception as it is occurring, but that verbal cues will be more powerful in retrospective judgments of deception. A final experiment will examine the cues an observer gives off that may inadvertently allow actors to be more effective liars.